The New River is 400 years old next year. So not really 'new' then. And since it is a man-made waterway, I don't think you could call it a 'river' either. However, in spite of its completely inaccurate name, it has an important functional and amenity value and is of particular significance to me. Not only does it flow right through N4, almost at the end of my road, but my Uncle Robert wrote a book about it – the only one I believe. In it he describes how the project managers, first Edmund Colthurst and then Hugh Myddleton, overcame all kinds of technical, financial and political difficulties to ensure the 42 mile long water course would slope incredibly gently, only dropping 13cm for every mile, to bring fresh water into London. Here's a map of the route it now takes, much less convoluted than the original.

The New River was opened on September 29th 1613 with a ceremony at the final destination in Clerkenwell, just near Sadlers Wells Theatre. This was presided over by the Lord Mayor of London, who happened to by Myddleton's brother. Over the years, various improvements were made and in the 1830s two massive reservoirs where built and then in the 1850s, a somewhat over-engineered pumping station and filter beds were added. East and West reservoirs are still there, the pumping station became the Castle Climbing Centre (here's the engineer, William Mylne's, modest wall plaque) and the filter beds are now an estate that backs onto my garden. The roads are called Colthurst Crescent and Myddleton Avenue after the project managers. The New River pretty much stops here and is still part of Thames Water's network as well as being section 12 of London's Capital Ring Walk.

The history of the New River highlights the ingenuity and perversity of human behaviour. In the 1600s we had an abundant water supply called the River Thames, but we were polluting it so badly we decided to transport water from 20 miles away using a complex and expensive engineering system that took years to build. If permaculture had been invented then, we would have found a much more intelligent way of dealing with the problem, at source. As Wendell Berry puts it:

If I urinated and defecated into a pitcher of drinking water and then proceeded to quench my thirst from the pitcher, I would undoubtedly be considered crazy. If I invented an expensive technology to put my urine and faeces into my drinking water, and then invented another expensive (and undependable) technology to make the same water fit to drink, I might be thought even crazier. It is not inconceivable that some psychiatrist would ask me knowingly why I wanted to mess up my drinking water in the first place. (Foreword, The Toilet Papers, Ecological Design Press, 1977, p9)

We now also understand that critical elements for plant fertility, such as phosphorus, are peaking in production in much the same way that oil is – current estimate is 2030. The phosphorus that is taken up by plants, from soil or fertilizers (eaten by us, digested and excreted) is lost forever when it is flushed down the toilet and so peak phosphorus should be of serious concern to anyone thinking about the future food supply for, well, not even as far away as our grandchildren. I hope I am showing here that the issues of water supply, human 'waste' and plant nutrition are inter-related. As such, any solution needs to look at the bigger picture and deal with these issues holistically.

The way to prevent the loss of phosphorus and other elements, is to use urine as a fertilizer, and we need to find sensible ways to do this right now. One really simple way to do this is to apply wee directly (without letting it sit around) onto cropping plants. If the plant is a big plant growing in the ground (rather than in a pot), there's plenty of woodchips on the surface and we're not in drought conditions, it's okay to add it neat. If this isn't the case then it should be diluted in 8 parts of water. Obviously you wouldn't do this with low growing leafy plants such as lettuce and you need to ensure you don't over do it. To give a very rough idea of how much is enough, Martin Crawford calculates that a mature apple tree would need one pee a week during the growing season to obtain all its nitrogen needs. (Creating a Forest Garden, Green Books, 2010 p54)

At Edible Landscapes London, the plant nursery, we have a brightly painted marker which we move around to show which plant needs wee next. In order to avoid some poor sod having to carry around a bucket of everyone's wee, we have our own wee catchers, dubbed "NPK collection units" after the elements Nitrogen, Phosphorus and Potassium which are found in wee. We might decide to put all our wee onto a comfrey patch and use that as a plant food. Or put it onto our compost heap. The point is to use it.

As for the less attractive solid waste, we need to find a way to compost it so it gets hot enough for the helpful thermophilic bacteria to kick in and deal with the pathogens. It then becomes usable as a soil improver, but it takes time and space to do this. So, fundamentally, when you look at the quantity of people living in London, there's clearly far too much poo being generated per square metre of land! But rather than working out how we can transport this away (using our drinking water) we should be questioning the logic of having such a high population density in the first place. A cursory examination of the supply and demand of our basic needs – water and 'waste' being just one inter-related example – reveals that London is almost entirely dependent on external supplies which are, in turn, dependent on fossil fuels, which we know are running out. As I say, we need to tackle this at a systemic level.

The New River is 400 years old and we've learnt a lot since 1613. However, we still want to celebrate the ingenuity of its construction and its importance as an amenity which can be freely enjoyed by everyone in our area. If our funding bid is successful, we will be marking the anniversary of its opening, whooping it up with a big celebration that will bring people together to get to know their area still better. However it's also worth mentioning that there are plans afoot to convert the toilets at the aforementioned Castle Climbing Centre, to compost toilets. And that, I believe, is the way forward. Hopefully it will demonstrate how we can redress the follies of our past.